Power actuator



c. s. BRAGG r-:TM

royan Acumon Original Filed Novfl, 1924 3 Sheets-Sheet 1 Aug. 16, 1927.

c. s. BRAG E1' AL POWER ACTUATQR 5 Sheets-Sheet 3 I origina; Fi1ed Nov.1, 1924 rasata; Aug.v 16, 1921. 4'UNITED STATES 1,639,285 PATENT oFlFlc-E.

CALEB s. BBAGeor rALx' BEACH, rLonIDA, AND vrc'ron w. xLI'EsnAfrH, or roar wAsnrNefroN, Nnw Yoan, AssIaNons 'ro-BnAss-xLmsnArn conroaArIoN, or LONG ISLAND crrY, NEW you, A conroBA'rroN or Nawv Yoan.

POWER ACTUATOB.

Original application led November 1,

Our invention .consists in the novel features hereinafter described, reference being had tothe accompanying drawings which. illustrate one embodiment of the invention, selected by us forpurposes of illustration, and the said invention is fully disclosed in the following description and claims.

Our invention relates to power -actuators for use in connection with automotive vehicles operated by or containing an internal combustion engine having a forced feed llubricating system, including .a pump and oil circulating passages connected therewith, and it consists in the provision of a power actuator including a cylinder, apiston working therein, an yactuated part connected with the piston and reversingv valve mechanism, and operatoroperated means for vthe reversing valve mechanism, said actuator audits reversing valve mechanism being operatively connected with the forced feed lubricating system of the internal com` *bustion engine, sothat the liquid under pressure necessary for the operation of the power Vactuator is supplied from the lubrlcating system of the engine-under the control of 'the reversing valve mechanism and its operator operated means.-

Practically all motors employed in connection with automotive vehicles, such as passenger cars, mot-or buses, motor trucks and the like, and many other types of motor propelled vehicles operable on land, in 0r upon water or inthe air, are provided with forced feed lubricatingsystem including an oil pump which pumps thek oil continually under a comparatively high pressure substantially thirty pounds or upward, through circulating pipes tothe various bearings of the engine, from which the oil finds its way back to a sump or reservoir and is used over and over again. In order to maintain an adequate supply of Aoil under .pressureffor lubricating the various bearingsunder Vvall conditions of ythe oil, l,which .becomes thin when heated or from use (crank vcase dilution) 'and undery all conditions of the bearing surfaces, which, when warm, permit a greater amount of oil to pass through them, it is customary toprovide a-:pump of far greater capacityv-thanfnormally neededl and to insert in the pressure line from the pump a by-pass leading back to the sump or reser- 1924, Serial No. 747,271. l 3, 1928. Serial No. 92,089. I

Divided and this application med latch voir and containing a regulating valve vwhich w1ll open when the predetermined pressure in the circulating lubricating system `is obtained, and by-pass the excess oil pumped back to the reservoir or sump.

In carrying our invention into effect, we draw upon the forced feed lubricating system of the engine asI a source of power for operating the power actuator. As the operation of the actuator is intermittent and its action and operation extend through ver short periods of time, an extremely smal quantity of pressure liquid is required 'to operate 1t, as compared with the capacity of the pump, and we have ascertained by practical demonstration thatvthe actuator-can be operated, 1n carrying out ourV invention, by means of oil under pressure from the lubrieating system of an ordinary automobile engine without in any way interfering with the operation of the lubricating system or reducing the pressure or the quantity of oil delivered to themotor bearings to such jan extent as to in any way impair the proper lubricating action on the engine.

In carrying our invention into effect, we prefer to connect the pressure pipe line leadlng to the actuator, to the by-passy of the engine lubricating system, so that, `as amatter of fact, the oil which is actually used in, the operation of the actuator, lis excess oil beyond the normalV requirements of the lubricating system, and does not impair its efficiency.

In 'the specific embodiment of our invention herein shown and described, we have gone further for the purpos'exof :preventin vpossible injury tothe engine, andto this en we prefer to employV in theby-pass of the lubricating system of the engine, an. adjust)- able pressure regulating valve, which" we term a safety valve, which is set to open at `a predetermined pressure below which it would be undesirable to operate""`tle engine, and a second pressure[regulating valve yis `also provi-ded between the safety valve andtheoil reservoir,- which isset at the normal vpressure'usually'maintainedfin such. oil Acirculating systems, the l pipe line through the actuator being ftappedfintothe by-passbet'ween said'v'alves.` From this construction it follows that so long asl the oil circulating system is working properly, vthere will'ordinarilybe ample pressure available for the o eration of the actuator without 1n any way iminishing the supply of oil to the engine. In case of complete failure of the oil circulating system, so that there is no pressure of oil to operate the actuator, the piston thereof can be'opera'ted by hand, by

lmeans of connections between the operator ning it with linsuiiicient lubrication.

operated part and the piston, providing a limited amount of lost motion, suilicient to operate the reversing valve mechanism, and thus enabling-the piston to be positively moved by the operator operatedpart when this limited amount of lost. motion is taken vup in either direction. Obviously, the failure of l'power to operate the actuator imposing upon the operator the necessity of moving the piston by his own physical force, would immediately communicate tothe operator a warning that the actuator was not functioning b power and that an examination of the oilyreservoir and lubricating system was necessary to prevent injury to the engine which would ot erwise result b -runcase of partial failure of the lubricating system,

- so as not to wholly destroy the oil pressure in the lubricating system, and where such ressure remains at or falls below that for w ich the safety valve in the by-pass is set, no pressure would be available for, and no oil would be used by the actuator, and no damage could by-pass of the oil circulating system to the actuator, constructed to remain open and permit the passage of oil under normal conditions, but effective to instantly close in case of a break in the pressure line leading to the actuator, which would reduce pressure on one side of the valve and permit it to be instantly closed against its spring bythe pressure of oil from the circulating system, thereby preventing loss of oil pending the making of necessary repairs. Weprefer to employ a power actuator comprising a cylinder, a double acting piston working therein,

and valve mechanism -for admitting the pressure fluid to either end ofthe cylinder, that is to say, on either side of the piston, said valvemechanism 'being so constructed that when it is in neutral position, the pressure fluid is cut oil' from both ends of the cylinder and at the saine time, a communicating actuator.

the oil lby-pass or passageis established, which willv permit the oil to How from one side of the piston to the other, preferably through the piston, to -enable the iston to be moved manually without the aid of, or interference from the actuator when the valve mechanism is in neutral position. We also 'prefer to provide means for normally maintaiiiin the valve mechanism in neutralpos'ition and for automatically returning it to neutral position after it has been moved out of neutral position in either direction, so that if for any reason the'valve operating mechanism should become broken, there would be no danger of an improper actuation of the piston of the We also prefer to provide air vents to prevent the formation of partial vacuum on the vpressure side of the piston when the valves are in. operative position, to cause the movement ofthe piston and for anyreason, such as the stalling of the motor,

ressure fails.

Our invention also comprises other novel features hereinafter particularly pointed out in the following Vdescription and claims.

In the accompanying drawings which il' lustrate one embodiment of the invention, selected by us for purposes of illustration, we have vshown an installation in an automotive vehicle in which the actuator is employed for thepurpose of operating the steering niecha- Y nism of the vehicle, but it is obvious that the actuator could readily be employed -to effect the operation of any piece of mechanism in or about the vehicle to` which the piston of the power actuator was properl connected, as the brake mechanism, clutci mechanism or other movable part. The specific features herein shown and described,

which relate to steering mechanism for auto*A mot-ive vehicles, are not specifically claimed herein as they form the subject matter of our prior application for Letters Patent of the United States, filed November 1, 1924, andv given Serial No. 747,271, of which this application is a division.

In the laccompanying drawings,

Fig. 1 represents a side elevation of a portion of an automobile chassis, the engine,

represented diagrammatically, the front.

wheels and steering mechanism therefor, showing a power actuator for the steering mechanism operatively connected with the forced. feed lubricating system of the engine. l

Fig. la repre on the line vl--la of Fig. 1.

Fig. 2 is a top plan View of the parts illustrated in Fig. 1.

Fig-3 is a detail sectional view on the line 3--3 of Fig. 1. t Y

Fig. 4 is an enlarged sectional View illustrating one form of power actuator and 'its connections with the steering mechanism and the manually operated control therefor.

sents a vertical sectional view Fig. 4. ,j

Inthe accompanying drawings, 1, repre-l sents the chassis of an automotive vehicle; vwhich may be of any usual or desired conl and is provided-with steering wheels, indicated at 2-2. In connection with these steeringwheels, we have shown struction,

j lthe ordinary manner of mounting and connecting' thesame for joint actuation, al-

"though it is 'to be understood that our invention is applicable to any form ofsteering mechanism. In, the present instance -the wheels are mounted on stub axles, 3, having vertical pivotal portions, 4, forming with their bearings, 5, the usual steering knuckles, eachggixle being provided with a steering arm,6,.and said arms being connected by an equalizing rod, 7, in the usual Imanner.

' One of the axles is provided with the usual steering lever, 8, to which the usual drag link, 9, is connected in any usual or preferred ,mannen For the. purpose `of securing the manual' control of the-steering mechanism,

either with or without the assistance of the actuator, hereinafter described, we 'have shown the usual steering wheel, 10, secured to the upper end of a steering shaft, 11, provided on its lower end with a worm, 12, engaging the usual worm segment, 13, -on a horizontal shaft, 14, provided with a downwardly extending arm, 15, which is connected with the drag link and the piston of the power actuator directly, and is also connected as iei'einafter explained, with the reversing valve mechanism of the actuator ,in such manner that the steering mechanism can be operated either'with or without the assistance of the actuator by turning the l rod, we prefer to mount the cylinder of theA ,actuator pivotally with respect to the chassis steering wheel, 10. To this end the rear end of the drag link, 9, is provided with a sleeve, 16, adapted to accommodate, a hard-1 cned ball, 17, at the lower end of the arm,

15. The upper side of the sleeve, 16, is provided with a slot, 18, through which the arm, 15, passes, so as to accommodate a slight movement of the arm, 15, with respect-to the sleeve. Within the sleeve, 16, we provide a pair of springs, 19, 20, located on opposite sides of the ball, 17, and engaging hardened wear-plates, 21-21, having recessed surfaces' to engagethe ball, 17. 'At the rear end of nthe sleeve, 16, is provided adjusting means 4 in the form of a screw plug, 22, which is screwed into the sleeve so as to compress both of the springs, y19-2(), to the same extentv and hold-the wear-plates, 21, firmly in Contact with the ball, 17.

When there is no physical'power applied toithe steering wheel or other manually opei'ated1,`devicc, these springs, 19 and 20, are

suiciently strong to maintain the valve mechanism of the actuator, in neutral position with respect to the piston. These springs may be so designed that when compressed to their-full extent, they form stops to prevent further movement of the valve vactuating mechanism with respect to the piston, andqthus prevent injury to the valve mechan ism. 'We prefer to provide'each of said springs with a washer provided with a stop (12F-20a, respectively) to engage the adjacent wear-plate and limit the movement of 4thedr'ag link actuating arm with respect to the sleeve toy a predetermined amount, sufficient lto insure the full opening. of thevalve mechanism in either direction, and prevent-. ing the valve-mechanism from being strained or in j uredy by physical force applied to the steering wheel. l A Y rfhe plug, 2 2, is held in adjusted position by a lock nut, 23. From the description of the parts thus far given, it will be seen that when. the hand-wheel, 10, is turned in one direction or the other, the arm, 15, will ,be moved either forwardly or rearwardly,

as the case may be, andtliat if the resistance of the steeringmechanism is not sufficient to cause the compression of the springs, 19 or 20, (according to the direction in .which the arm, 15,'moves) the steering mechanism will operate under the manual control of the operator exactly as any ordinary steering mechanism operates. l

30 represents the actuator cylinder which is supported from the chassis inreanof the y arm, 15, and drafr link, 9, connected therewith, the cylindertbeing provided with heads, {iL-connected by suitable bolts, 32. In order to permit the piston rod of the actuator to be connected directly to the drag link in alignment with the axis of its pivotal connection Awith the arm, 15 and to avoid the usev of universal joints in valve actuating tolaccommod'ate the slight variations .in the position ofthe piston rod, to accommodate the arc of travel of the ball, 17, `and to this lthe actuator piston which is double' acting,

and ispreferably provided with oppositely extending gaskets, as shown. 37 represents theA piston rod, which extends through a stuffing box, 38, at the forward end of the actuator cylinder, and has its forward end connected with the sleeve, 16. ln this instance, the plug, 22, is provided with an exi tension, 22, to which the forward end of the piston rod is positively connected by a pin, 39. By reason of this construction, 1t will be observed that thepower actuator, when in use, is applied to the drag link 1n exact alignment with the-point at which the power of the hand operated lever, 15, applies power to the drag link.

lhe actuator' piston is provided with a reversing valve mechanism for controlling the admission and eduction of oil, and in this instance we have shown a reversing valve mechanism including rotatable valves. The particular form of valve mechanism herein shown and described is not claimed herein as it is covered by a separate application tiled .bv us November 6, 1924, and given Serial No.

' respectively with the passages, 4t) and 41, to

which are connected respectively pressure inlet pipe, 42, and the outlet pipe, 43. The central portion ol the piston is provided with a passage, 44, and with a parallel passage, 45, said passages forming continuations respectively' ,of the passages 41 and40 in the .piston rod. 4Inline with each of the pas sages',v 44 and 45, is a conical valve seat, 46 and 47, respectively. The valve seat, 46, is provided with an outlet port, 4S, opening on the rear side of the piston, and with an outlet port, 49, opening on the opposite or forward side ot the piston. The valve seat, 47, is provided with an inlet port, 50, communicating with the cylinder in rear of the piston, and an inlet port, 51, coinn'iunicating with the c vlindcr forward of the piston by means et a longitudinal passage, 52, and a transverse or .iiigiilarpassage, indicated at 53. ln the conical valve seats are located rotary vthree-way valves, indicated at 54 and 55, re-

spectively, each of which is provided with a valve stem, 56, suitably mounted in the piston and provided with coil springs, 57, for holding the valves in their conical seats. l'lach of the valve stems is provided with a pinion, 58, :for rotating it, said pinions meshing with racks, 59, on opposite sides of a will be noted that the outlet passage, 44, is not in communication with either of the outlet ports, 48 and 49, and the inlet passage, 45, is not in communication with either of the inlet ports, 50 or 51. Obviously, when the valve is in this position, the actuator' is inoperative. nism may be operated by handvat all times when the reversing valves are in neutral position, we provide means for establishing a passage through the piston from one side to the other, so that the oil may pass from one end of the cylinder through the piston to the other end of the cylinder, to accommodate movements of the steering mechanism by hand. To this end we have shown herein the valve seat, 46, provided with auxiliary ports, 62 and G3, the former communicating with the cylinder at the rear of the piston, and the latter communicating with the cylinder forward of the piston through the pas-l sages, 52, 53, said ports being so located as to be brought into direct communication through the three-way passage in the valve, 54` when the latter is in its neutral or normal position, as clearly shown in Fig. 5. 'I hese auxiliary ports may be made of considerable cross sectional area, so as to allow the oil to vpass through very freely, in which ca se the actuator piston would ofer very slight resistance when the reversing valves are in neutral position and the steering mechanism-i is operated by hand. If it is desired to have the piston of the actuator provide a retarding effect on the actuation of the steeringl mechanism by hand, and also to act to a certain extent as a dash-pot or shock absorber to prevent accidental or sudden movements of the steering mechanism, as might occur if one of the steering wheels struck a large stone or obstruction, or dropped into a deep hole lor soft portion of the road, the cross sectional area of the aux iliary ports, 62 and (33, can be reduced to any extent which may be found desirable. 'Obviously the smaller the cross sectional area of these passages, the greater will be the efeet of the piston in retarding the hand operated movements of the steering wheels, and the greater will be its elfect as a dashpot or shock absorber.

l/Ve also prefer to provide means for-nor` mally holding the reversing valves in their neutral positions so that thc valves will be returned to neutral position after each actuation and will be normally held therein in case of the breaking of the valve actuating means hereinafter described. In the present instance, we have shown the valve actuating rod, GO, provided with a pair of coil springs,

In order that the steering mecha-v 64, arranged on opposite sides of a collar, 65,

secured to the piston by a cotter pin, 65a, extending through brackets, 36a, projecting from one end of the piston, said pin extending through a longitudinal slot, 60a, in the australes .tween said collar and shoulders, (S6-67, on

the valve actuating rod, 60, see Fig. 11, so that whenever the rod, 60` is moved longitudinally so as to actuate the rotary valves, one or the other of thesesprings will be compressed and will tend, to return the rod and valves to neutralrposition. Any other suitable mechanism for this purpose may be employed.

Referring now to Figs. 5, 6 and 7, it will be understood that if the valve rod, 60, is movedforward vor to the left, the valve, 54, will be rotated clockwise, so as tobring the outlet passage, 44, into communicationwith the outlet port, 49, and ,close the auxiliary ports, 62 and 63. At the saine time the rotary valve, 55, will be moved counter-clockf wise, so as to bring the port, 50, into comvniunication with the inlet assage, 45. The

pressure liquid will imme'iately pass into the cylinderin rear of the piston and cause the piston to move forward, the liquid in -the Cylinder forward of the piston being forced out through the passage, 41, and returned to the sump, as hereinafter explained. The movement of the piston will,

therefore, follow the movement of .the `actuating rod. As soon as the actuating rod stops the continued movement of the piston will cause it to move relatively with respect to the rod, 60, and restore the valves to neus tral position. If the rod, 60, is moved rearwardly or to theright, the valve, 54, will be rotated counter-clockwise, so as to connectthe outlet port, 48, with the passage, 44, while the valve, 55, will be rotated clockwise so as to connect the inlet port, 51, with the inlet passage, 45, thereby admitting pressure fluid to the cylinder forward of the iston and discharging liquid from the cy inder in rearl of the piston and causing the piston to travel backward until the rearward movement of the rod, 60, ceases', when the continued movement of the piston, with respect to the rod, restores the valves to normal position, and'reestablishes the throughpassage,'62-63.

. In order to effect the longitudinal movement of theivalve actuating rod, 60, we provide the drag link` operating lever, 15, with a lateral arm, 7-0, see Fig. 3, the lower end of which is pivotally connected at 71, with a link bar, 72, extending to the rear end of the valve actuating rod, 60, where lit is PlVotally connected to a bracket arm, 73, secured to the rod, 60. We prefer to provide the cylinder with `.suitable slotted guides, in-

dicated at 74, through which this link rod passes, in order that the rod may be prevented from falling to theground and improperly operating the actuator incase it' i should become disconnected from thearm,

70. For convenience in attaching the actuator to existing steering mechanism, the

arm and may be secured to the ordinaryworm actuated lever, 15, as indicated in Fig. 3. Obviously, it may be made in one piece with the arm, 15, if desired, and in either case the Iaxis'of the ivotal connection, 71, should be in' line with the center of the ball, 17, at the lower end of the arm, 15.

Referring now to the sleeve, 16,- and the oppositely arranged springs, 19 and 20, therein, on opposite sides of the ball, 17, it will be understood that when the hand wheel, 10, is turned, if the resistance offered by the steering wheels and connected mechanism is so slight that the said wheels respond without compression either -of the springs, 19 or 20, as the case may be, according tothe direction in which the wheel is turned, it is obvious that the piston of the actuator, the valves of which are in neutral positionfwill simply move in the cylinder displacing a small quantity of oil from one side of the piston to the other, and the rod,

60, will move .the piston without altering 'o' 9 its position longitudinally with respect thereto. Consequently, the`valves will remainin neutral' position and the wheels will be steered by hand power without bringing the actuator into operation at all save as it may exert a slight retarding influence and serve as a dash-pot to a greater or less extent, according to the cross sectional area of the through-passage, provided by ports, 62-63. If, however, the resistance to the turning movement of the wheels is suiiciently great as turning slowly .and in passin overrutty or uneven ground or soft groun so that the wheels do not instantly respond to the physical force exerted by the operator on the steering wheel, one of the springs, 19--20, as the case may be, will be compressed by the movement of the arm, 15, thus producing a" movement of the valve actuating rod, 60, with respect to the piston, and when this relative movement is suicient to rotate the valves into either of their operative positions, the piston will instantly respond andproceed to move under the force of the pressure fluid, moving the piston rod and steering movement, therewill be no load ony the springs, 19'-2O, and the springs will restore the valve to neutral, position, as heretofore described. If, forany reason thev power of the actuator alone1 should' be insuliicient to effect the steering movement desired, the physical force of the driver will thel driver or operator, to effect be added to the power of the actuator in effecting the desired movement.

The particular steering arrangement herein shown and described is not herein claimed as it forms the subject matter of `our prior application filed November 1, 1924, and

'ven Serial No. 747,271, hereinbefore re'- erred to.

The pressure fluid which in this instance is lubricating oil, required for 'the operation `of the actuator, is supplied from the forced feed oil system of the internal combustion engine, which provides the source of power for the operation of the actuator when the latter is called into use. In the accompanying drawings, for example, we have indicated more or less diagrammatically the motor or engine at 80, which is an internal combustion engine provided with the usual forced feed lubricating system. This system comprises a pump, 81, which pumps the lubricating oil from a reservoir or sump, indicated at 82, in the bottom of the crank case, through a pipe, 84, or pipes, which supply the oil under pressure to the bearings` and to the parts of the engine or motor, as indicated in dotted lines at 83 in Fig. 1. 94 represents a by-pass leading from the pipe, 84, back to the lower portion of the crank case and discharging surplus oil, above the requirements of the circulating system to the oil reservoir, or sump. 86 represents a relief valve,` which we term the safety relief valve, which is inserted before the pipe, 84, and the by-pass, 94. This valve is preferabl an adjustable spring actuated ball relie valve, shown in detail in Fig. 10, the ball valve being held closed by a spring, 86, the tension of which may be adjusted, as by a screw threaded hand operated device, 86", for example. A second adjustable relief valve, 85, is preferably arranged in the bypass, 94, as shown, between the safety reliefvalve, 86, and the oil reservoir, or sump. This relief valve, 85, is shown in detail in Fig. 8, andA likewise is provided with the ball Valve having an adjustable spring tension normally holding it in closed position.l ln practice, we prefer to set the safety relief valve, 86, at a minimum pressure, below which it vwould not be considered safe to operate-the engine, and to set the relief valve, 85, -to the maximum pressure which is ordinarily desired to be maintained-in the4 circulating lubricating system. We arrange to take the pressure oil-for operating the power actuator from thev by-pass between the relief valves, 85 and 86, as indicated in Fig. 1, in which the pressure supply pipe, 42, is so connected, and extends to the passage, 40, in the piston rod, 37 of the actuator.

In order to accommodate the longitudinal movements of the piston rod, it is necessary to insert a flexible section of pipe, indicated at 87, in the pipe, 42, as shown in Fig. 1.

The outlet pipe, 43, from the piston rod is I connected to the sump or "oil reservoir, and is likewise' provided with an intermediate flexible portion, 88. It follows from this construction that the pressure in the by-pass, 94, between the valves, 85 and 86, will normally be the maximum pressure maintained in the circulating system, and this is available for the operation of the actuator. As the operation thereof is intermittent, and extends through extremely short periods, only a little oil is withdrawn momentarily from the circulating system to operate the actuator', and by this arrangement the oil which is so withdrawn is excess oil beyond the normal requirements of the circulating lubricat-in system. As before stated, in case of comp ete failure of the circulating system,

there would be no pressure of oil to operate the actuator, and the steering mechanism in such case can be operated by hand, but will require greater force on the part of the driver or operator. This would instantly warn the driver or operator that the actuator was not functioning and that an examination of the lubricating system would be necessary to avoid injury to the engine. If there is a partial failure only of the lubricating system, so that the pressure in the system falls to or below the pressure for which the safety valve, 86, is set, there would -be no pressure available for the actuator and the actuator would not withdraw any oil from the lubricating system, so that there would be no danger of injury to the motor by the attempted use of the actuator. ln

.such case also, the drivers attention would be called to the condition of the oil circulating system by the failure of the actuator to properly function. We also prefer to provide an additional valve, 89, in the pressure Huid pipe, 42, leading to vthe actuator, which is of the well known type of normally open spring actuated valve, as shown in Fig. 9, for example, in which the valve is held open by a spring so long as pressures are substantially equal on opposite sides of the valve. rThis valve will be so arranged as to be instantly closed against its spring in case the connection of the pipe, 42, withthe actuator should break or leak, thereby shutting od' power fluid to the actuator and preventing it from being wasted. lf such accident should occur, this would also result in putting the actuator out of operation, but l the steering mechanism may nevertheless be operated by hand in the usual manner and the failure of the actuator would be immediately communicated to the driver by the increased amount of power Which it would be necessary for him to exert in steering, so that he would have an opportunity to at once ascertain the nature and extent of damage and make the necessary repairs.

In carrying out our invention, we have provided not only a construction which is operable at -the will of the operator under any and all conditions, when there is variable pressure to operate the actuator, but 'also a construction 'in'wlnchmeans are 'provided forpreventing any improper' operation of the actuator incase ofrfaccident, and also for prevcxitingfthe actuator from 1 n any way" interfering/withfthe-manual lll operation of the steering mechanism in case- .the actuator itself bccomeslfincapacitated. Forv example,"if lthe steering Wheel were being operated'. uli-der conditions sufficiently strenuous'to compress one of the springs, iti-20, andset the reversing valves, ,for movementl in one direction, and should 'the supply of motor iiuid under pressure i fail, as by breaking of the pump or stalling `of the engine, the' operator could effect the continuedmovement of the steering mechanism by means of the `hand operated mechf anism, but as the through passage, or by-pass, of the piston would be'closed, the movement of the actuator would force a certain" quan-` tity of oil out of thecylinder into the sump,

or reservoir, without material re'istance, but

on the other side of the piston, the oil would not be supplied readily and a partial vacuum might be caused, which would interfere with the ready operation of the steering mech-A anism by hand under such .circumstances.

In order to obviate the possibility of the formation of 'a partial'vac-uum ywithin the cylinder under such-conditions, or any other conditions, we prefer to provide means for venting inwardly both ends of the cylinder. This can be effected in several ways, of which two are illustrated in the accompanying drawings. For instance. the venting means can be applied tothe inlet and voutlet` pipes,

.42 and i-3 by providing the pipe,4;2, with an ordinary check valve., such as a. ball check valve. indicated at 892L iii Fig. :4. adapted -to open inwardly. The pipe, is p referably connected to the crankgcase or casing of the engine ahovethelevel of fthe oil therein, as indicated in Fig. 1,'"50 that this ventsthe pipe. 43, and lprevents'the..formation of a partial vacuum therein Weprefer., however. out of abundant caution, to provide each end of the cylinder with a.` check "valve, such as a ball check valve,`as indicated at 90-90, in Fig. .4, for example, .so

'that under the circumstances above referred to, air will enter either end ofthe cylinder in case thereisany dangerof formingfa partial vacuum, so. as not to interfere wit-li the manual operation Vof the steering mechs anism when thefreversing valve is in one of its operative positions. Any air so admitted would be expelled in the normal operation of the actuator and if air should accumulate at any time in the cylinder,l it can be released by operating` the actuator and temporarily opening the auxiliary air valves,

`an. actuated part connected with the piston,

reversing: valve mechanism, and operative connections from said oil circulating system to said reversing-'valve mechanism for supplying pressure luid'for the operation of saida'ctu'ator and apressure regulating valve interposed between the saidli'ibricating .sys-

tem'and the connection leading therefrom to the 'reversing valve mechanism, constructed to cloe said connection when the "pressurein the lubricating system falls below a predetermined pressure, to prevent the 'reduction of pressure in the lubricating system .I

below said predetermined pressure 'by the operation of said actuator.

2.. In an automotive vehicle provided with feed lubricating system therefor, including a pump and oil circulating passages connectan internal combustion engine, and a forced'v ed therewith, ofa power actuator including -7 a .cylinder and a piston working therein, an

actuated part connected with the piston, and

reversing valve mechanism, said oil circulan' ing); system including ahy-pass' for returning excess lubricating'oil to the pump without passing through the lubricating passages,

Vand provided with a pressure regulatin l valve .interposed between said by-pass an 'g the pump, and connections between said bypass and the reversingl valve mechanism of the actuator for supplying motor liquid..

therefor, whereby the supply of motor liquid to the actuator will be excess oil bey-ond thef' normalfrequirements of the engine.

3'. In an automotive vehicle provided with? "lio an internal combustion engine, and a.' forced feed 'lubricating system therefor,including A a `pump and oil circulatingpassagesgcounecte `-ed. therewith, Iof a power actuator including a cylinder ,and a pistonworking therein, an actuated parteonnect-ed with the piston, and

:reversing valve mechanism,`said lubricating;

system including a. by-pass ,for condueting` the excess .oil to the oil -Iemilfjf'tyl valve in said bye-pass adaptedlto-elosewlien the pressure in the circulating'system falls i below a safe pressure yforfftlua',.,eiigii'i'e',' and a second safety valve forinaintinighhigher normal `pressure inithe lubii ""systein l ot the engine, and conni-ictio'n's'#fromv a ypointin said by-pass between said valves*4 to the reversing valve mechanisrnrof the actuator. 4. In an automotive vehicle'provided .with an internall combustion engine` and a forced feed 'lubricating system therefor, "including lll a pump and oil circulating passages connected therewith, of a power actuator including a cylinder and a piston-working therein,

an actuated part connected with the piston, and reversing valve mechanism, said oil circulating lsystem including a by-pass for returning excess lubricating oil to the pump without passing through the lubricating passages, and provided with a pressure regulating valve Ainterposed between said ley-pass and the pump, and connections between said by-pass and the reversing valve mechanism of the actuator for supplying motor liquid therefor, whereby the supply of motor liquid to the actuator will be excess oil beyond the normal requirements of' the engine, and a valve in said connection, normally held open by a spring and adapted to be closed by pressure 1n case of a reduction of pressure between said valve and the actuator.

5. In an automotive vehicle provided with an internal combustion engine and a forced feed lubricating system therefor, including a. pump, an oil reservoir, oil circulating lubricating passages, a liv-pass for returningexcess lubricating oil to the reservoir without passing through the lubricating pasthe actuator, containing provision for lost motion sufficient to insure the operation of the reversing valve mechanism, whereby on failure of power, the operation of the operator operated device will transfer the load of the piston and the part to be operated thereby, to the operator and apprize him of the reduction of pressure in the lubricating system.

G. In an automotive vehicle provided with an internal combustion engine and a forced feed lubricating system therefor, including a pump, an oil reservoir, oil circulating lubricating passages, and a by-pass for returning 'excess lubricating oil to the reservoir without passing through the lubricating passages, :i pressure regulating valve interposed betweenY the pump and said by-pass for disconnecting the by-pass from the pump when the` pressure in the circulating lubricating system falls below a pre-determined point, below which it is undesirable to operate the engine, a second regulating valve in said bypass beyond the first .mentioned regulating valve, constructed to close when the pressure in the by-pass falls below the predetermined normal pressure which it is desired 'mechanisim whereby in case of undue reducto maintain in the circulating lubricating system, of a power actuator including a cylindcrand a piston working therein, and reversing valve mechanism for thefactuator, an actuated part connected with vthe piston, pipe connections communicating with said y-pass between said regulating valve, and extending to said reversing valve mechanism of the actuator, an operator operated device for the reversing valve mechanism, and connections between the operator operated device and the piston of the actuator, containing provision for lost motion suicient to -insure the operation of the reversing valve tion of pressure in the oil circulating system, or failure of pressure in saidsystem, the operation'of the operator ope 'ated device'will transfer the load of the piston and the part to be operated thereby, to the operator and apprize him of lthe reduc-tion of failure of pressure in the lubricating system.

7 In an automotive vehicle, provided with an internal combustion engine and a forced feed lubricating system therefor, including a pump, an oil reservoir, oil circulating lubricating passages, and a by-pass for returning l excess lubricating oil to the reservoir, and a pressure regulating valve for said by-pass, of ,a power actuator including a cylinder, a piston working therein, and reversing valve mechanism, an actuated part connected with the piston, pipe connections extending from said by-pass to said reversingr valve mechanism, an operatoroperated 'device for said reversing valve mechanism, and connections between the operator operated device and the piston of the actuator, containing provision for lost motion sufficient to insure the operation of the reversing valve mechanism, said reversing valve mechanism being constructed to close communication with said lubricating system when the valve mechanism is in normal position, and being provided with a communicating by--pass to permit the oil within the cylinder to flow vfrom one side of the piston to the other` when the valve mechanism is in the normal position. l

8. In an automotive vehicle provided with an internal combustion engine, and a forced feed lubricating system therefor, including a pump, an oil reservoir, oil circulating lubricating passages, and a by-pass for returning excess lubricating oil to the reservoir, and a pressure regulating valve for said bypass, of a power actuator including a cylinder, a piston working therein, and reversing valve mechanism, an actuated vpart connected with the piston, pipe connections extending from said ley-pass to said reversing valve mechanism, an operator operated device for said reversing valve mechanism, and connections between the operator operateddevicev and the piston of the actuator containing provision for lost motion sucient to inwith said lubricating system when the valve mechanismis in normal position, and being provided with a communicating by-pass to permit the oil within the cylinder to flow from one side of the piston to the other, when the valve mechanism is in the normal position, and yielding means for normally maintaining the reversing valve mechanism in normal position.

9. In an automotive vehicle provided with an internal combustion engine and a forced feed lubricating system therefor, including an oil reservoir, a pump, and oil circulating passages connected therewith, of a power actuator comprising a cylinder, a piston therein, and reversing valve mechanism, means for connecting the piston with an actuated part, inlet connections from said oil circulatin system, and the said reversing valve mec anism, a pressure regulating valve constructed to close said inlet connection when the pressure in the lubricating stem falls below a predetermined point, an outlet connections from said valve mechanism for said reservoir for returning oil thereto from the actuator.

10. In an automotive vehicle lprovided with an internal combustion en 'ne and a' v `forced' feed lubricating system t erefor including an oil reservoir, a pump, an oil passage connected therewith, a power actuator comprising a cylinder, a piston therein, and

reversing valve mechanism, means for con-- necting the piston with a part to be actuated, inlet connections from said oil passage to said valve mechanism, including a p pressure controlled element constructed to insure an adequate supply, of oil to said lubricating system, outlet connections from said valve mechanism to said reservoir, and means or-returnin surplus oil from saidv oil passage above t e requirements of the lubricating system to the reservoir.

11. In an automotive vehicle provided with an internal combustion en ineand a forced feed lubricating system t erefor in. cluding an oil reservoir, a pump, an oil passage connected therewith, a power actuator comprising a cylinder, a piston therein, and reversing valve mechanism, means for connecting the piston with a part to be actuated, inlet connections from said oil paage to said valve mechanism, outlet connections from said valve mechanism to said reservoir, a pressure valve inter osed) between .said oil passage and the said valve mechanism, constructed to close communication therebetween when the pressure in the lubricating system falls below a predetermined point,

and means for returning surplus oil from said oil passage beyond the-requirements of the lubricating system to the said reservoir.

In testimony whereof we aix our signatures.

CALEB S. BRAGG. VICTOR W. KLIIESRATH.I 

